diff --git a/src/codec/flag.rs b/src/codec/flag.rs
new file mode 100644
index 0000000..b341ea5
--- /dev/null
+++ b/src/codec/flag.rs
@@ -0,0 +1,31 @@
+use libc::c_uint;
+use ffi::*;
+
+bitflags! {
+	flags Flags: c_uint {
+		const UNALIGNED       = CODEC_FLAG_UNALIGNED,
+		const QSCALE          = CODEC_FLAG_QSCALE,
+		const _4MV            = CODEC_FLAG_4MV,
+		const OUTPUT_CORRUPT  = CODEC_FLAG_OUTPUT_CORRUPT,
+		const QPEL            = CODEC_FLAG_QPEL,
+		const GMC             = CODEC_FLAG_GMC,
+		const MV0             = CODEC_FLAG_MV0,
+		const INPUT_PRESERVED = CODEC_FLAG_INPUT_PRESERVED,
+		const PASS1           = CODEC_FLAG_PASS1,
+		const PASS2           = CODEC_FLAG_PASS2,
+		const GRAY            = CODEC_FLAG_GRAY,
+		const EMU_EDGE        = CODEC_FLAG_EMU_EDGE,
+		const PSNR            = CODEC_FLAG_PSNR,
+		const TRUNCATED       = CODEC_FLAG_TRUNCATED,
+		const NORMALIZE_AQP   = CODEC_FLAG_NORMALIZE_AQP,
+		const INTERLACED_DCT  = CODEC_FLAG_INTERLACED_DCT,
+		const LOW_DELAY       = CODEC_FLAG_LOW_DELAY,
+		const GLOBAL_HEADER   = CODEC_FLAG_GLOBAL_HEADER,
+		const BITEXACT        = CODEC_FLAG_BITEXACT,
+		const AC_PRED         = CODEC_FLAG_AC_PRED,
+		const LOOP_FILTER     = CODEC_FLAG_LOOP_FILTER,
+		const INTERLACED_ME   = CODEC_FLAG_INTERLACED_ME,
+		const CLOSED_GOP      = CODEC_FLAG_CLOSED_GOP,
+	}
+}
+
diff --git a/src/codec/mod.rs b/src/codec/mod.rs
index 18aa93c..e3e9ac3 100644
--- a/src/codec/mod.rs
+++ b/src/codec/mod.rs
@@ -1,3 +1,6 @@
+pub mod flag;
+pub use self::flag::Flags;
+
 pub mod id;
 pub use self::id::Id;